Specific-gravity balance.



N0. 808,421. PATENTED DEC. 26, 1905. I. M. WILLIAMS. SPECIFIC GRAVITYBALANCE.

APPLICATION FILED THE. 7. 1905.

INVENTORI v m Prank nLWiHiams,

Fig.2.

By ,q M,

Att

UNITED STATES rarnn'r orrron I SPECIFIC-GRAVITY BALANCE.

Specification of Letters Patent.

Patented Dec. 26, 1905.

Application filed February '7, 1905. Serial No. 244,596.

To all whom, it may concern.

Be it known that I, FRANK M. WILLIAMS, a citizen of the United States,residing at Potsdam, county of St. Lawrence, State of New -York, haveinvented certain new and useful Improvements in Specific-GravityBalances, of which the following is a specification.

My invention relates to balances for determining the specific gravity ofsubstances; and its object is to provide a balance of this typecomprising. a number of useful features not heretofore found in suchinstruments.

One type of specific-gravity balance well known in the art is known asthe lVestphal balance. This instrument comprises, essentially, a pivotedbeam carrying at one end a pointer and at the other a plummet of fixedweight and volume which is immersed in the liquid the specific gravityof which it is desired to measure and its buoyancy in that liquidmeasured by means of weights or ri ers adjusted on the pivoted beam.

One feature of my invention consists in arranging a balance of thisgeneral type so that it may conveniently be employed for meas uring thespecific gravity not only of liquids, but of solids as well. Iaccomplish this by suspending from the opposite end of the beam fromthat from which the usual plummet is suspended two pans or receptacles,one above the other, adapted to receive the solid to be measured andproviding a suitable counterweight readily adjusted. By immersing thelower pan in water or other suitable liquid and by placing the solidfirst in one pan and then in the other and measuring its weight in eachcase by'means of riders properly adjusted on the opposite end of thebeam the loss of weight on immersion in water is quickly and accuratelyascertained. From this loss of weight the specific gravity may becalculated in the wellknown manner. The range of utility of the balanceis thus greatly increased by extending it to the measurement of solidswithout in any way diminishing its convenience or accuracy in themeasurement of the specific gravity of fluids.

Another feature of my invention consists in the supporting means for thelower pan, consisting of a spring-clip which holds the pan firmly andprevents its floating from the support when being immersed.

Another feature of my invention consists in forming the arm from whichthe pans are suspended with a screw-thread and providing a screwthreaded counterbalance and lock nut adapted to travel on said arm,whereby an exceedingly close adjustment is conveniently obtained andmaintained.

Another feature of my invention consists in a novel arrangement forlifting the pivoted beam from its supporting knife-edges and firmlylooking it, so that the pans, plummet, 620., may be lifted off andreplaced and the instrument moved about without injury to theknife-edges and without entirely removing the beam from itssupporting-standard. Another feature of my invention consists in a novelarrangement for folding the instrument to render it more portable andeasily packed and for firmly looking it when folded.

Other features of my invention will ap ear from the followingspecification and wi 1 be more specifically pointed out in the appendedclaims.

My invention Will best be understood by reference to the accompanyingdrawings, in which Figure 1 is a side elevation of a balance arranged inaccordance with my invention. Fig. 2 is a plan view of the same. Fig. 3is a side elevation of the balance when folded for packing. Figs. 4 and5 are detail views of the means for lifting the pivoted beam from itsbearings, and Fig. 6 is a'per'spective view of the pan-holder.

In the drawings, U represents a supportingstandard provided with theusual levelingscrew it and carrying the hollow rod or tube P. Supportedwithin rod P and vertically adjustable therein by means of the set-screw79 is the rod Rigidly secured to the upper end of rod Q is the member V,which carries at one end the scale 1 and at the other end the casting W,on which the working parts of the instrument are supported. This castingis provided with j ewel-bearings R, (shown in Fig. 4,) adapted toreceive the knifeedges O, which support the pivoted beam J. One arm ofbeam J is formed as a pointer opposite scale 12, and the other endcarries a pin L and hook m, fromwhich is supported the usual thermometerplummet M. This end of beam J is calibrated and notched, as shown, toreceive the usual riders X or other suitable weights.

The general construction as thus far described is the same as that ofthe Westphal balance. The plummet M is so proportioned in weight andvolume that when it is immersed in water at a certain temperature andwhen a rider of a certain size is placed on the hook m the beam J willassume a horizontal position. When the plummet is immersed in anotherliquid, the riders are adjusted until a balance is secured and thespecific gravity is thereby indicated.

In order to permit the measurement of solids, I provide a notch A at theopposite end of beam J and a hooked wire I, adapted to engage and besuspended from that notch. This wire, which is clearly shown inperspective in Fig. 6, carries supports for two pans S and T, (shown inFig. 1,) arranged one above the other, so that one pan may be submergedin water or other liquid, while the other pan is in air. The support forthe lower pan is preferably formed as a spring-clip, as indicated inFig. 6, so that the lower pan is firmly held and preventedfrom floatingfromits support when it is being immersed. The arm J is formed with ascrew-thread, as shown, and a counterweight, formedin two parts B B, isarranged to travel on the screw-thread. The screw-thread allows of afine adjustment, and the two parts of the counterweight act as lock-nutsto hold each other in place.

The method of procedure for obtaining the specific gravity of solidswith the instrument arranged as above described is as follows: Theplummet is suspended from one end of the beam J and the empty pans fromthe other, the lower pan being immersed in water, and with the ridersremoved the two-part counterweight is adjusted to bring the beam to ahorizontal position. The substance to be measured is then placed in theupper pan S, the riders adjusted to balance its weight, and the weight,as indicated by the riders read and recorded. The substance is thenmoved to the lower pan and the riders again adjusted. The difference inthe two readings gives the loss of weight in water, and the specificgravity may be calculated in the usual manner. If the substance is suchthat its composition would be altered by immersion in water, any othersuitable liquid may be employed. The specific gravity of that liquid maythen be determined by immersing the plummet in it in the usual mannerand this value used in calculating the specific gravity of the solid.

A single wire is employed for supporting the lower pan, and .this wireis made as small as is consistent with the necessary stiffness in orderthat .the amount of water adhering to the wire and carried above thesurface, as the wire moves up and down with the oscillations of thebeam, may be so small as to have no effect on the accuracy of thereadings. Since the only changes between making the two readings consistin shifting the substance from the upper pan to the lower and adjust ingthe riders, all sources of needless error are eliminated.

In the use of the balance it is necessary frequently to lift the plummetout of the liquid in which it is immersed to remove and replace the pansor perhaps to move the instru* ment from one place to another. All thesemovements may injure the knife-edges or jewels if the pivoted beam isleft on its sup port, and to remove the beam and replace it is equallylikely to result in injury and is also inconvenient. I avoid thesesources of injury by providing means for lifting the beam from itsknife-edge support, locking it firmly in its raised position, and gentlylowering it again into its bearings when desired. The pin D,providedwith a suitable knurled head, carries the cam K, (shown in dotted linesin Figs. 1, 3, and 4,) which is normally inoperative. When it is desiredto lift the beam from its bearings, the cam K is rotated, raising thesoring H, the free end of which presses against the cam into engagementwith beam J and lifting the'beam into engagement with the pointed screwsC. The beam J may be provided with pits on its upper edge adapted to beentered by the points of the screws C, so as to lock the beam firmly inits raised po sition, as shown in Fig. 3. If spring H were notinterposed between cam K and beam J, the rotation of the cam would tendto shift the beam longitudinally; but the presence of spring H removesthis shifting tendency.

For conveience in packing I so arrange the instrument that it may befolded so as to occupy a small space. For this purpose the stem or rod Qis ointed, being formed of two parts pivoted at E. A sliding collar F,provided with a suitable set-screw, securely locks the two portions ofrod Q either in line with or at right angles to each other, as shown inFigs. 1 and 3, respectively. The operation of this device will beevident from an inspection of the drawings and requires no furtherdescription.

It will be obvious that my invention comprises a number of featureswhich while I prefer to use them together may with advantage be usedseparately and which I desire to claim whether used together or not.Accordingly I do not desire to limit myself to the particularconstruction and arrangement of parts here shown, but aim in theappended claims to cover all modifications which are within the scope ofmy invention.

What I claim as new, and desire to secure by Letters Patent of theUnited States, is

1. In a balance, a pivoted beam having one arm graduated and adapted toreceive weights or riders and having its other arm screw-threaded, aplummet suspended from the graduated arm, a counterweight adapted totravel on the screw-threaded arm, a member removably suspended from thescrew threaded arm, and a plurality of pans or receptacles supported bysaid member.

2. In a balance, a pivoted beam having one arm graduated and adapted toreceive Weights or riders and the other arm screwthreaded and arrangedat its outer end to form a pointer, a counterweight adapted to travel onthe screw-threaded arm, a fixed scale positioned opposite the end of thescrew-threaded arm, a member removably supported from saidscrew-threaded arm, a plurality of pans or receptacles supported by saidmember, and a plummet suspended from the graduated arm.

3. In a balance, a pivoted beam having one arm graduated and adapted toreceive weights or riders, a member removably supported from the otherarm of said beam, and provided with two supports one above the other,and two removable pans or receptacles carried by said supports, thelower support being formed as a spring-clip whereby the lower pan orreceptacle is held securely in place.

4. In a balance, a pivoted beam having one arm graduated and adapted toreceive weights or riders, a wire provided with a hook at its upper endadapted to engage the other arm of said beam and carrying two supportsone above the other, the lower support comprising a spring-clip, and twopans or receptacles adapted to be removably carried by said supports.

5. In a balance, a pivoted beam having one arm graduated and adapted toreceive weights or riders and having its other arm screw-threaded, aplummet suspended from the graduated arm, a two-part counterweightadapted to travel on the screw-threaded arm, a member removablysuspended from the screw-threaded arm, and a plurality of pans orreceptacles supported by said member.

6. In a balance, a pivoted beam provided with a knife-edge support, amanually-rotatable cam, a member secured against movement in a directionlongitudinal with respect to said beam adapted to be moved by said caminto engagement with the under side of said beam near said knife-edge tolift the beam from its support, and means for engaging the upper side ofsaid beam when said beam is lifted.

7. In a balance, a pivoted beam provided with a knife-edge support, amanuallyrotata ble cam arranged beneath said beam near said knife-edge,a leaf-spring secured substantially parallel with said beam with itsfree end bearing on said cam and adapted to be pressed against the lowerside of said beam when said'cam is rotated, and means for engaging theupper side of said beam when said beam is lifted from its support.

8. In a balance, a pivoted beam provided with aknife-edge support, amanually-rotatable cam arrangedbeneath said beam near said knife-edge, aleaf-springsecured substantially parallel with said beam with its freeend hearing on said cam and adapted to be pressed against the lower sideof said beam when said cam is rotated, and a plurality of pointedmembers adapted to engage the upper side of said beam when said beam islifted from its support, the upper side of said beam being provided withpits adapted to be engaged by the points of said members.

9. In a balance, a pivoted beam provided with a knife-edge support,manually-operated means for imparting a vertical pressure on theunderside of said beam near said knifeedge, and means for engaging theupper side of said beam when said beam is lifted from its support, saidbeam and said engaging means being provided the one with a plurality ofpointed members and the other with a plurality of pits adapted to beengaged by the points of said members.

10. In a balance, a pivoted beam provided with a knife-edge support,manually-operated means for imparting a vertical pressure on the underside of said beam near said knifeedge, and a plurality of pointedmembers adapted to engage the upper side of said beam when said beam islifted from its support, the upper side of said beam being provided withpits adapted to be engaged by the points of said members.

11. In a balance, a standard, a verticallyadjustable jointed rodsupported thereby, said rod comprising two pivotally-connected portions,means for locking said portions in line or substantially at right anglesto each other, and a pivoted beam supported by the upper of saidortions.

12. In a ba ance, a standard comprising a vertical tube, a jointed rodadjustably supported in said tube, said rod comprising twopivotally-connected portions, means for locking said ortions in line orsubstantially at right ang es to each other, and a pivotedbeam supportedby the upper of said portions.

13. In a balance, a jointed stem comprising two pivotally-connectedportions, a collar adjustably mounted on said stem and adapted to locksaid portions in line or substantially at right angles to each other,and a pivoted beam supported on the upper of said portions.

14. In a balance, a jointed stem comprising two pivotally-connectedortions, means for locking said portions in ine or substantially atright angles to each other, a normally horizontal pivoted beam providedwith a knife-edge and supported therefrom on the upper portion of saidstem, and means for lifting said beam from its support and looking it inraised position.

15. In a balance, a jointed stem comprising two pivotally-connectedportions, means for locking said portions in line or substantially atright angles to each other, and a normally horizontal pivoted beamsupported by the upper portion of said stem.

16. In a balance, a supporting-stem, a member pivotally carried therebyand movable through an angle of substantially ninety degrees relative tosaid stem, means for looking said'member in either of its extremepositions, and a normally horizontal pivoted beam supported by saidmember.

17. In a balance, a supporting stem, a member pivotally carried therebyand movable through an angle of substantially ninety degrees relative tosaid stem, means for looking said member in either of its extreme posirotions, a normally horizontal pivoted beam provided With a knifeedge andsupported therefrom on said member, and means carried by said member forlifting said beam from its support and looking it in its raisedposition. I 5

In Witness whereof I have hereunto set my hand this 4th day of February,1905.

F. M. WILLIAMS.

Witnesses:

WM. I-I. HAND, FRANK L. COLLINS.

